Schematic Reference: Headlights/Daytime Running Lights (DRL) Schematics

Connector End View Reference: Master Electrical Component List in Wiring Systems

1

Did you perform the Lighting System Diagnostic System Check?

Go to Step 2

Go to Diagnostic System Check - Lighting Systems

1. Turn ON the headlamps.
2. Position the headlamp dimmer switch in the low beam position.
3. Turn OFF the headlamps.

Do the low beam headlamps operate properly?

Go to Testing for Intermittent Conditions and Poor Connections in Wiring Systems

Go to Step 3

1. Disconnect the lamp control module (LCM).
2. Connect a 20-amp fused jumper between the headlamp low beam supply voltage circuit of the LCM and battery positive voltage.

Do both of the low beam headlamps illuminate?

Go to Step 4

Go to Step 5

1. Remove the fused jumper.
2. Connect a test lamp between the headlamp switch headlamps on signal circuit of the LCM and battery positive voltage.
3. Turn ON the headlamp switch.

Does the test lamp illuminate?

Go to Step 6

Go to Step 9

1. Disconnect the inoperative low beam headlamp bulb.
2. Connect a test lamp between the inoperative headlamp bulb headlamp low beam supply voltage circuit and inoperative headlamp bulb ground circuit.

Does the test lamp illuminate?

Go to Step 12

Go to Step 8

Test the ignition 1 voltage circuit of the LCM for a high resistance, a open or a short to ground. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 18

Go to Step 7

Test the ground circuits of the LCM for a high resistance or an open. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 18

Go to Step 13

Test the inoperative headlamp bulb headlamp low beam supply voltage circuit for high resistance, an open or a short to ground. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 18

Go to Step 14

Test the headlamp switch headlamps on signal circuit of the LCM for high resistance, short to ground or an open. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 18

Go to Step 10

Test the headlamp switch ground circuit for high resistance, short to ground or an open. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 18

Go to Step 11

Inspect for poor connections at the harness connector of the headlamp switch. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 18

Go to Step 16

Inspect for poor connections at the inoperative headlamp bulb. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 18

Go to Step 17

Inspect for poor connections at the harness connector of the LCM. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 18

Go to Step 15

Repair the open or high resistance in the inoperative headlamp ground circuit. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you complete the repair?

Go to Step 18

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Replace the LCM. Refer to Lamp Control Module Replacement .

Did you complete the replacement?

Go to Step 18

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Replace the headlamp switch. Refer to Headlamp Switch Replacement .

Did you complete the replacement?

Go to Step 18

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Replace the inoperative headlamp bulb. Refer to Headlamp Bulb Replacement .

Did you complete the replacement?

Go to Step 18

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Operate the system in order to verify the repair.

Did you correct the condition?

System OK

Go to Step 2